The present invention relates to methods and systems for controlling or managing digital control systems, and more particularly to methods and systems for compensating for measurement delays in sensor measurements performed during control of an electric motor.
Electrical power steering (EPS) systems in vehicles use an electric motor connected to the steering gear or steering column that is electronically controlled to provide a torque to assist a driver in steering the vehicle. EPS systems typically include an electric motor and controller that receives steering torque information from a torque sensor and controls the motor to transmit assist torque to the wheels, e.g., by applying the torque to the steering column. One type of motor is a Permanent Magnet (PM) brushless motor.
The controller typically controls the EPS motor by generating duty cycle signals for each motor phase, e.g., using pulse width modulation (PWM), which are used to provide phase voltage signals to the motor. For example, the controller receives measurements of the motor such as motor position and motor current, which are used to adjust the duty cycle signals. Delays in such measurements can cause errors and decrease stability of motor control systems.